OBSERVATION OF WHITE LIGHT-INDUCED DRIFT SEPARATION OF RB ISOTOPES

The observation of the separation of rubidium isotopes by white light- induced drift is reported. A broadband modeless laser with a smooth sp ectrum is used as a light source. Spectral structure formed by the tra nsport of light through the vapor causes a light-induced drift, pushin g the Rb-87 and pulling the Rb-85. The separation is measured by spect roscopic isotope analysis. Hyperfine effects are considered and reject ed as a possible source of a false separation signal. Also investigate d is whether statistical properties of the light beyond the time-avera ged intensity could produce a net drift. Although it is found that a n et drift is possible even for a flat time-averaged spectrum, this is n ot expected from the structure of the broadband laser used because the associated time scales are too short. The evidence indicates that the observed separation is due to the predicted white light-induced drift effect.